Nipple discharge can be caused by a number of conditions. It is important that it is assessed appropriately. Whilst most discharge is caused by benign conditions, rarely it can be a sign of early breast cancer, particularly if it is blood stained.
If occurring in both breasts it can be due to production of milk – either the result of normal lactation, due to hormonal imbalances (overproduction of prolactin, hypothyroidism) or the result of certain medications. Duct ectasia (dilation and inflammation of the ducts under the nipple) can also cause discharge from both breasts; it tends to be green-brown in colour. This is a benign condition.
Discharge from one duct on one nipple more commonly needs surgical treatment. The most common cause is a ductal papilloma (benign polyp of the duct). Other causes include duct ectasia and breast cancer ( 5% of cases of nipple discharge). Your surgeon will assess your nipple discharge and recommend appropriate management. This usually includes a mammogram and ultrasound and may include sending some of the fluid for assessment. This is known as cytology and is obtained by smearing the discharge on a glass slide. You may require a day surgery operation to remove the abnormal duct. This is called a microdochectomy.